Luminous tube



Patented July 11, 1933 UNITED STATES LEO L. BECK, OF WESTFIELD,

DELAWARE NEW JERSEY, GENERAL TUBE LIGHTS CORPORATION,

ASSIGNOR, BY MESNE ASSIGNMENTS, T0 01? NEW YORK, N. Y., A CORPORATION OF L'UMINOUS TUBE No Drawing.

This invention relates to a mixture of rare gases within a luminous tube which combine or blend their respective characteristic colors, emitted when illuminated, to produce a light which does not distort or does not materially distort the natural colors.

It is well known that a neon luminous tube which emits the characteristic orange red neon color is rich in red rays and is lacking in blue rays and it is an object of this invention to add a rare gas a tube which when illuminated emits a characteristic light having blue rays and the rays of the two gases blend to produce a light having both the red and blue rays or produces a light in which the characteristic spectra of each gas is visible.

The blue rays which must be added to the red rays of a neon luminous tube may be secured by mixing one or more gases having blue as the characteristic luminous color with neon which emits its characteristic red colored light. The mixture is in the proper proportions when the neon red color is is masked by the blue color and the blue colored light is masked by the red colored light. This relation or proportion may be expressed differently in this way, that the spectra of both gases are visible in the light emitted by the mixed gases. 1 have found that the rare gas krypton when mixed with neon produces a light which has blue rays and when mixed in the proper proportion with neon the mixture emits a light when luminous which does not distort the natural colors. The krypton supplies the blue rays which neon lacks when illuminated. It is to be understood that the neon gas referred to in this description may be neon alone or a mixture of neon with another gas or gases which, however, when illuminated will not affect the characteristic orange red color of the neon.

Krypton, when mixed with the neon so that the tube contents contain 1% or less of this gas in relation to the whole gaseous content of the tube, will produce a light when luminous in which the neon red color rays and the krypton blue color rays blend toemit a light which does not distort the natural colors. The pressure of the mixture of gases within the tube may be any of the pressures known tothe art.

The gas krypton has a low voltage gradient which enables a tube having a mixture of Application filed June 29,

to the neon gas within.

1929. Serial No. 373,918.

neon and krypton to be operated at a low voltage, such as is used in commercial power lines, and with relatively high currents which materially increase the luminosity of the tube. A potassium pool or a hot cathode electrode is preferably used where high currents andlow voltages are. applied to the tube. The low voltage characteristic of the gas enables the use of ordinary electrical devices and eliminates the use of heavily insulated equipment which is necessary where high voltages must be used for the operation of the tube. The low voltage gradient characteristic of the gas also results in a luminous tube which operates at a relatively low temperature.

What is claimed is 1. A positive column luminous tube light provided with electrodes comprising a mixture of neon and krypton in such porportions that the characteristic color of each gas is visible in the spectrum of the light emitted, the proportion of krypton being not more than one per cent of the mixture when the mixture is illuminated by direct or 'low frequency alternating current.

2. A positive column luminous tube light provided with electrodes comprising a mixture of rare gases including neon and krypton in which the neon and krypton blend their characteristic colors so that the characteristic spectra of each gas is visible in the light emitted, the portion of krypton being not eater than one per cent of the mixture of rypton and neon where the mixture is illuminated by direct or low frequency current.

3. A positive column luminous tube light, provided with electrodes comprising a mix ture of neon and krypton each of which emits its characteristic color when the mixture is illuminated by direct or alternating current, the krypton being approximately one per cent of the mixture of krypton and neon.

4. A method of producing a positive column light which does not distort natural colors comprising blending neon with about one per cent of krypton, and then rendering the gases luminous current through them. 7

In testimony whereof I aflix my signature.

LEO L. BECK.

by passing an electric 

